Ancient Reptile Glided on Air

June 13, 2007 - Late Triassic dinosaurs might have looked up to see a tiny, long-necked reptile gliding by, according to a research team that has identified such a creature.

The 220 million-year-old glider, Mecistrotrachelos apeoros, was probably a protorosaur, a group of ancient, long-necked reptiles that predated and later co-existed with dinosaurs. One member of this group, Tanystropheus, grew to 12 feet long, and half of that was neck.

Its newly discovered relative, which measured just 10 inches long, once soared over what is now the Virginia-North Carolina border. Scientists found two specimens embedded in separate blocks of hard slate and shale-like stone at a site there called the Solite Quarry.

Nick Fraser of the Virginia Museum of Natural History found the fossils, but he told Discovery News that he first thought they were bony fish tails.

"One day I was looking at the second specimen," he said, and "the sun radiated over what I thought were fish bones and I said to myself, 'This thing has a head and a long neck! It's a reptile!'"

To better analyze the finds, Fraser and colleague Tim Ryan conducted a CT scan at Penn State's Center for Quantitative Imaging. The scan revealed the "greeny-brown" reptile had unusual feet and ribs, in addition to its long neck.

Their findings are published in today's issue of the Journal of Vertebrate Paleontology.

"Reptiles typically have fairly long toes but, in this case, the feet are quite small," Fraser said. "They were also preserved in a hooked posture, so it is likely these were grasping feet belonging to a reptile adapted to arboreal existence."

The specimens also showed thickening in their upper ribs, which indicates "a reasonable amount of muscle" was once attached there to control skin flaps resembling wings.

The researchers doubt the reptile could flap these pseudo wings, but they do believe the muscles indicate the creature was no haphazard flier.

"It did not simply jump in the air from a tree on a wing and a prayer and hope to land on something soft," Fraser explained. "This reptile could maneuver and change direction while gliding."

While its feet and muscles aided such air adventures, the reptile's long neck is the real scientific head scratcher, since a tiny skull attached to the end of a long neck is subject to substantial friction in mid-glide.

Hans Sues, associate director for research and collections at the Smithsonian's National Museum of Natural History, was surprised when he first learned about the reptile's long neck. Most protorosaurs did not fly or glide, and most gliding reptiles didn't have long necks.

But, he added, "that doesn't imply it wasn't a good glider. Even some snakes today can glide their long bodies over long distances."

These flying snakes, all from the genus Chrysopelea, literally fling themselves from tree to tree while undulating their bodies to allow for somewhat smooth gliding.

A closer living match to the newly identified gliding reptile, at least in terms of lifestyle, is Indonesia's flying dragon lizard, which folds out wing-like layers of skin attached to its movable ribs before gliding between trees up to 25 feet apart.